1. Field of the Disclosure
The present disclosure relates to hand tools and more particularly, to a screwdriver which has a driver bit holder like a revolving wheel-shaped clip, for placing multiple driver bits of various forms. Driver bit holder can be rotated like rotating a clip to choose driver bits of different forms in operation.
2. Discussion of the Background Art
The screwdriver of prior art mostly has its driver rod extended forward from the handle, and the front end of the driver rod forms a driver bit or places a driver bit. When needing to use different forms of driver bits for work, the user has to replace the screwdriver or replace the driver bit, which is inconvenient. Each of U.S. Pat. No. 6,134,995A, U.S. Pat. No. 6,138,537A and U.S. Pat. No. 7,028,593B1 claims to protect a screwdriver. They all have driver bit holder similar to revolving wheel-shaped clip, for placing multiple driver bits of different forms. The driver bit holder can be rotated like rotating a clip when in use, to change driver bits of different forms. But the defects reside therein that:
1. Complicated structure;
2. The handle needs to be detached from the mounting position of the driver bit holder when the driver bit of the driver bit holder is to be replaced, which is inconvenient to operate;
3. When screwing, the handle is used to apply forward force to tightly push the pushrod so as to apply torque to screws, and the pushrod can easily retract;
4. The applied torque is restricted by the mating structure of the handle and the mounting position of the driver bit holder. As the mating structure is generally plastic, the torque is therefore limited;
5. The position that the driver bit holder and the pushrod coincides is shielded, which will shield the view of a user to hamper replacing the driver bit accurately;
6. Inconvenient to replace the driver bit holder, therefore inconvenient to replace the driver bit on the driver bit holder either;
7. Lacking positioning of the driver bit holder, the pushrod cannot accurately coincide with the driver bit mounting hole on the driver bit holder, so the driver bit cannot be smoothly pushed out;
8. As the effect of the driver bit is to apply torque to a screw, and the body of the driver bit is mostly hexagonal prism, so the shape of the inner hole of the driver bit sleeve that it mates should be fit with the shape of the driver bit. Further, in order to smoothly push out the driver bit, the hole (e.g. the containing hole on the driver bit holder, the inner hole of the driver bit sleeve and so on) that is used to contain driver bit mates the driver bit with gaps. So during the process of pushing the driver bit out, the front end of the driver bit (especially as shown in FIG. 33 the ‘−’ shaped front end of the driver bit, the maximum size of the front end identical to that of the driver bit) will deviate from the inner hole of the driver bit sleeve so as to be hard to be pushed in; further, when the surface of the driver bit body deviates by a certain angle from the inner hole of the driver bit sleeve, it is also hard to push the driver bit into the inner hole of the driver bit sleeve; the scenarios above that the driver bit cannot be pushed into the inner hole of the driver bit sleeve will cause the screwdriver unusable.
Accordingly, it is an object of technicians in this field providing a screwdriver which is simple-structured, convenient to use, and can smoothly push out the driver bit.